This invention relates to an improvement on a tape recorder such as a video tape recorder and a digital audio tape recorder. More particularly, the present invention relates to an improvement on a tape draw-out mechanism for drawing out a tape from a tape cassette and winding a predetermined length of the tape around a rotary drum in a tape recorder such as a video-tape recorder and a digital audio tape recorder in which a tape is drawn out from the tape cassette and is wound around the rotary drum for recording and reproduction. This invention also relates to an improvement on a drive system in a video/digital audio tape recorder. This invention relates to an improvement on a cassette mounting device for mounting a tape cassette in a tape recorder such as a video tape recorder and a digital audio tape recorder. The present invention also relates to a main brake mechanism for preventing reel stand from rotation in a brake of a tape recorder such as a video tape recorder, a digital audio tape recorder and a compact tape recorder.
In a tape-recorder of this kind such as a digital audio tape recorder, a rotary drum is slantingly provided on a chassis. In order to wind a tape around the slanting rotary drum, the tape must be wound at a position lower than that of the tape cassette.
For this, the tape position must be elevated to the position of the tape cassette for taking up the tape at the tape cassette, since the tape passing over the rotary drum is positioned lower than the tape position in a reel stand in the tape cassette.
For the elevation of the tape position, according to a conventional tape draw-out mechanism a single tape draw-out pin 35d is provided at a guide member 35 for raising the position of the tape wound around the rotary drum to a raised position and then the tape is directed in horizontal direction as shown by a phantom line in FIG. 23. Therefore a long distance L is required from the terminal end position of the drum 4 to a tape pull-out pin 35d. However the large length L is disadvantageous in realization of the compact tape recorder.
Also in a conventional tape recorder, there are provided a tape draw-out unit which includes a pinch roller, a tension regulator, a guide member movable along the outer peripheral surface of a rotary drum, and a third guide member supported on a capstan shaft and movable in association with the pinch roller. The draw-out members all start movements simultaneously, and all stop movements simultaneously.
Therefore, tape withstand from a complicated path is travelled through a complexed path for winding the tape by a predetermined length over the rotary drum. Particularly, in case where the rotary drum is slantingly directed as seen in the digital audio tape recorder, it would be troublesome to perform positional alignment between the tape and the rotary drum. Therefore, a more complexed device is required rendering the overall mechanism complex.
According to a conventional tape recorder, tape loading is made for recording and reproducing information with a tape, tension is applied to the tape, and the tape is conveyed at a constant speed. Further a chassis must be moved for providing a compact tape recorder.
However, in the conventional tape recorder, at least two motors are required for controlling these various operations. Therefore, it would be difficult to adjust sequential timing for moving various segments. If the timing is deviated or offset, it becomes impossible for recording and reproducing information. Further, great numbers of segments (motors) are required, to increase production cost.
According to a conventional tape recorder of this kind, a single motor performs various operations to reduce production cost.
Therefore, since the single motor controls mode switching as well as tape loading, it would be difficult to precisely control braking operations in accordance with various modes. Further it takes much time for switching operation in the mode switching operation, and accordingly, smooth mode change may not be obtainable.
In a tape recorder such as video/digital audio tape recorder in which a tape is withdrawn from a tape cassette, the pinch roller is pivotally moved to a predetermined position at the tape withdrawing operation, and then, the pinch roller is again moved to be brought into pressure contact with the capstan in the reproducing operation.
Therefore in such a conventional tape recorder, the above described pinch roller drive system is not applicable.
In a conventional mechanism for press contacting a pinch roller with a capstan, a single member is operated, or, alternatively, dual operational stages are provided in which the pinch roller is brought to a position close to the capstan by moving a head slide having a head in a first operational stage, and the pinch roller is pressed against the capstan by a rotational force of an arm movable by a suitable drive means in a second operational stage.
In a tape recorder such as a video tape recorder and a digital audio tape recorder, a movable chassis having a tape drive means such as reel stands etc. mounted thereon, is slidingly movable on a stationary chassis having thereon a capstan and a magnetic head mounted thereon. In this conventional structure the movable chassis is moved on the stationary chassis during the tape loading operation where the tape cassette is mounted in the movable chassis, or after the loading. For mounting the tape cassette onto the movable chassis, a cassette holder is used.
According to a conventional cassette holder, there is provided a first holder portion, a second holder portion and a locking means. The first holder portion is provided on the movable chassis for directly holding the tape cassette and for assembling the same onto a reel stand. The second holder is provided on the stationary chassis for holding the first holder and for opening and closing the same and for urging the latter to a predetermined position. The locking means is provided on the stationary chassis for maintaining closing state of the second holder.
Therefore, since the first and second holders and the locking means are provided in the cassette holder, large numbers of mechanical parts are required assembling work becomes troublesome, and production cost is increased. Further, heavy weight product results which is not appropriate for portable tape recorder.
In a tape recorder, two main brakes are provided for a supply reel and a take-up reel. The two main brakes must be spaced away from the reel stands in quick feed, rewinding, forward play and reverse play modes. Further, the brakes must be in pressure contact with the reel stands in the stop mode. Furthermore, the main brake must be in pressure contact with one of the reel stands (for example, a supply reel stand) for withdrawing a tape from the reel stand and for winding the tape in tape loading or unloading mode.
According to a conventional brake mechanism, one of the main brake is controlled by a cam, so that the other main brake is moved by the main brake, whereby both brakes are cooperably pressed against the reels, or spaced away therefrom. Further, in the tape loading or unloading mode, one of the main brakes is moved away from the reel by another mechanical member.
In the conventional brake mechanism, required are a slider having a cam for controlling the brakes and other segments for controlling one of the brakes. As a result, a large number of mechanical segments are required to thereby increase production cost. Further, overall mechanism becomes complex, and the mechanism may apt to be damaged.